images in respiratory medicine
Venous air embolism from blunt chest trauma Cheryl R Laratta MD1, Lawrence Cheung MD FRCPC1,2 A 73-year-old woman was involved in a high-speed motor vehicle collision on a highway. When the ambulance arrived, the woman was found to be in pulseless electrical activity (PEA). Cardiopulmonary resuscitation was initiated and, although return of spontaneous circulation was initially achieved after 4 min, the patient went into PEA arrest three additional times until arrival to the emergency department. After an initial chest x-ray (Figure 1), a computed tomography (CT) scan of the chest revealed a large amount of air in the main pulmonary artery (Figures 2A and 2B, and Figure 3), with small amounts of air present in the right atrium, right ventricle, left and right brachiocephalic trunks (Figure 4), proximal superior vena cava and left subclavian vein. A left first rib fracture, bilateral pneumothoraces and left subclavian vein hematoma were present; trauma to the left subclavian vein was believed to be the source of the air embolism. Although hyperbaric oxygen and aspiration of the air under right heart catheterization were considered, the patient stabilized with mechanical ventilation and vasopressors. A CT scan of the chest 6 h later showed virtually complete resolution of the air in the vessels and heart, and the patient was discharged from hospital two months later.
• Venous air embolism may cause PEA by leading to transient ‘air lock’, pulmonary outflow tract obstruction, and diminished or absent cardiac output. • Potential therapies include hyperbaric oxygen, aspiration of the air, left lateral decubitus head-down positioning and supportive care (3).
A
Key learning points • Penetrating or blunt chest trauma can cause venous air embolism (1-3). Other causes include central line insertion, barotrauma during mechanical ventilation, bronchoscopic laser therapy, needle biopsy of the lung or other procedures (1,3). • CT scans may suggest the source of air entry in the setting of multiple injuries.
B
Figure 1) Initial anterior-posterior supine chest x-ray
Figure 2) Axial chest computed tomography mediastinal windows (A) and lung windows (B) showing air in the main pulmonary artery (arrows)
1Division
of Pulmonary Medicine, University of Alberta; 2Division of Critical Care Medicine, University of Alberta, Edmonton, Alberta Correspondence: Dr Lawrence Cheung, Department of Medicine, University of Alberta, 11350 83 Avenue, Edmonton, Alberta T6G 2G3. Telephone 780-492-4039, fax 780-492-4483, e-mail [email protected] Can Respir J Vol 22 No 4 July/August 2015
©2015 Pulsus Group Inc. All rights reserved
199
Laratta and Cheung
Figure 4) Axial chest computed tomography revealing air in the left and right brachiocephalic trunks (arrow) References
1. Thomas AN, Stephens GB. Air embolism: A cause of morbidity and death after penetrating chest trauma. J Trauma 1974;14:633-8. 2. Baker CC, Thomas AN, Turnkey DD. The role of emergency room thoracotomy in trauma. J Trauma 1990;20:848-55. 3. Ho A, Ling E. Systemic air embolism after lung trauma. Anesthesiology 1999;90:564-75.
Figure 3) Sagittal chest computed tomography revealing air in the main pulmonary artery (white arrow) and right ventricle (black arrow) The ‘Images in Respiratory Medicine’ section of the Canadian Respiratory Journal aims to highlight the importance of visual interpretation, whether physiological, radiological, bronchoscopic, surgical/thorascopic or histological, in the diagnosis of chest diseases. Submissions should exemplify a classic, particularly dramatic or intriguing presentation of a disease while offering an important educational message to the reader (insightful diagnostic pearls or differential diagnosis, etc). This section is not intended to be a vehicle for publication of case reports (see the Clinico-Pathologic Conferences for case-based leaning series).
200
Can Respir J Vol 22 No 4 July/August 2015
Venous air embolism from blunt chest trauma Cheryl R Laratta MD1, Lawrence Cheung MD FRCPC1,2 A 73-year-old woman was involved in a high-speed motor vehicle collision on a highway. When the ambulance arrived, the woman was found to be in pulseless electrical activity (PEA). Cardiopulmonary resuscitation was initiated and, although return of spontaneous circulation was initially achieved after 4 min, the patient went into PEA arrest three additional times until arrival to the emergency department. After an initial chest x-ray (Figure 1), a computed tomography (CT) scan of the chest revealed a large amount of air in the main pulmonary artery (Figures 2A and 2B, and Figure 3), with small amounts of air present in the right atrium, right ventricle, left and right brachiocephalic trunks (Figure 4), proximal superior vena cava and left subclavian vein. A left first rib fracture, bilateral pneumothoraces and left subclavian vein hematoma were present; trauma to the left subclavian vein was believed to be the source of the air embolism. Although hyperbaric oxygen and aspiration of the air under right heart catheterization were considered, the patient stabilized with mechanical ventilation and vasopressors. A CT scan of the chest 6 h later showed virtually complete resolution of the air in the vessels and heart, and the patient was discharged from hospital two months later.
• Venous air embolism may cause PEA by leading to transient ‘air lock’, pulmonary outflow tract obstruction, and diminished or absent cardiac output. • Potential therapies include hyperbaric oxygen, aspiration of the air, left lateral decubitus head-down positioning and supportive care (3).
A
Key learning points • Penetrating or blunt chest trauma can cause venous air embolism (1-3). Other causes include central line insertion, barotrauma during mechanical ventilation, bronchoscopic laser therapy, needle biopsy of the lung or other procedures (1,3). • CT scans may suggest the source of air entry in the setting of multiple injuries.
B
Figure 1) Initial anterior-posterior supine chest x-ray
Figure 2) Axial chest computed tomography mediastinal windows (A) and lung windows (B) showing air in the main pulmonary artery (arrows)
1Division
of Pulmonary Medicine, University of Alberta; 2Division of Critical Care Medicine, University of Alberta, Edmonton, Alberta Correspondence: Dr Lawrence Cheung, Department of Medicine, University of Alberta, 11350 83 Avenue, Edmonton, Alberta T6G 2G3. Telephone 780-492-4039, fax 780-492-4483, e-mail [email protected] Can Respir J Vol 22 No 4 July/August 2015
©2015 Pulsus Group Inc. All rights reserved
199
Laratta and Cheung
Figure 4) Axial chest computed tomography revealing air in the left and right brachiocephalic trunks (arrow) References
1. Thomas AN, Stephens GB. Air embolism: A cause of morbidity and death after penetrating chest trauma. J Trauma 1974;14:633-8. 2. Baker CC, Thomas AN, Turnkey DD. The role of emergency room thoracotomy in trauma. J Trauma 1990;20:848-55. 3. Ho A, Ling E. Systemic air embolism after lung trauma. Anesthesiology 1999;90:564-75.
Figure 3) Sagittal chest computed tomography revealing air in the main pulmonary artery (white arrow) and right ventricle (black arrow) The ‘Images in Respiratory Medicine’ section of the Canadian Respiratory Journal aims to highlight the importance of visual interpretation, whether physiological, radiological, bronchoscopic, surgical/thorascopic or histological, in the diagnosis of chest diseases. Submissions should exemplify a classic, particularly dramatic or intriguing presentation of a disease while offering an important educational message to the reader (insightful diagnostic pearls or differential diagnosis, etc). This section is not intended to be a vehicle for publication of case reports (see the Clinico-Pathologic Conferences for case-based leaning series).
200
Can Respir J Vol 22 No 4 July/August 2015
